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everywhere obsoured by slope detritus, or lies along

a fault. Prom exposurea slightly to the north, in

the area mapped by J~hns. it is known that the Modelo

is present as a thin wedge between Mint Canyon and

Saugus strata, narrowing and disappearing to the east.

The same relat1onah1p is known to exist toward the south.

llong the south side of Plum. Canyon, the

lowest Modelo horizon visible is a hard, brown cobble

conglomerate. This probably oorresponda to the

persistent basal oonglomerate mentioned by Jahns,(7

and is therefore interpreted as representing the base

or the Modelo 1n that area. It is overlain by thin

layers 0£ well-bedded gray to tan siltstone and tine-

grained sandstone with a tew persistent horizons ot a

tougher, dark bro'Wl'l sandstone. Soattered grains and

anhedral masses ot gypsUlll ooou.r in the finer beds.

The exposures further west, on the northern

side of Plum. Canyon, show bedded gray sandstones and

pebble oonglomerates with some oonsp1ouous layers of

brown sandstone. These gray beds oloaely resemble

some exposures ot Mint Canyon strata, but the brown

sandstone is distinctive, and tb.e aeries oan be traced

northward into the area mapped by Jahns where it overlies

the Kint Canyon formation with a visible unoontormity.

(7 - R.H. Jahns, op. cit.